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    <title>加减法口算练习系统-v0.2</title>
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    <h1>加减法口算练习系统-v0.2</h1>
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    <div class="exercise-container">
        <div class="exercise">
            <span class="number">1. </span>
            <span class="expression">60 - 1 = ?</span>
            <div class="answer">答案: 59</div>
        </div>
        <div class="exercise">
            <span class="number">2. </span>
            <span class="expression">66 - 40 = ?</span>
            <div class="answer">答案: 26</div>
        </div>
        <div class="exercise">
            <span class="number">3. </span>
            <span class="expression">2 + 62 = ?</span>
            <div class="answer">答案: 64</div>
        </div>
        <div class="exercise">
            <span class="number">4. </span>
            <span class="expression">58 - 29 = ?</span>
            <div class="answer">答案: 29</div>
        </div>
        <div class="exercise">
            <span class="number">5. </span>
            <span class="expression">97 - 23 = ?</span>
            <div class="answer">答案: 74</div>
        </div>
        <div class="exercise">
            <span class="number">6. </span>
            <span class="expression">21 + 16 = ?</span>
            <div class="answer">答案: 37</div>
        </div>
        <div class="exercise">
            <span class="number">7. </span>
            <span class="expression">76 - 72 = ?</span>
            <div class="answer">答案: 4</div>
        </div>
        <div class="exercise">
            <span class="number">8. </span>
            <span class="expression">59 + 36 = ?</span>
            <div class="answer">答案: 95</div>
        </div>
        <div class="exercise">
            <span class="number">9. </span>
            <span class="expression">75 - 20 = ?</span>
            <div class="answer">答案: 55</div>
        </div>
        <div class="exercise">
            <span class="number">10. </span>
            <span class="expression">38 - 27 = ?</span>
            <div class="answer">答案: 11</div>
        </div>
        <div class="exercise">
            <span class="number">11. </span>
            <span class="expression">66 - 8 = ?</span>
            <div class="answer">答案: 58</div>
        </div>
        <div class="exercise">
            <span class="number">12. </span>
            <span class="expression">61 - 4 = ?</span>
            <div class="answer">答案: 57</div>
        </div>
        <div class="exercise">
            <span class="number">13. </span>
            <span class="expression">91 - 57 = ?</span>
            <div class="answer">答案: 34</div>
        </div>
        <div class="exercise">
            <span class="number">14. </span>
            <span class="expression">95 - 72 = ?</span>
            <div class="answer">答案: 23</div>
        </div>
        <div class="exercise">
            <span class="number">15. </span>
            <span class="expression">62 - 25 = ?</span>
            <div class="answer">答案: 37</div>
        </div>
        <div class="exercise">
            <span class="number">16. </span>
            <span class="expression">85 - 84 = ?</span>
            <div class="answer">答案: 1</div>
        </div>
        <div class="exercise">
            <span class="number">17. </span>
            <span class="expression">69 - 9 = ?</span>
            <div class="answer">答案: 60</div>
        </div>
        <div class="exercise">
            <span class="number">18. </span>
            <span class="expression">73 - 19 = ?</span>
            <div class="answer">答案: 54</div>
        </div>
        <div class="exercise">
            <span class="number">19. </span>
            <span class="expression">63 - 20 = ?</span>
            <div class="answer">答案: 43</div>
        </div>
        <div class="exercise">
            <span class="number">20. </span>
            <span class="expression">47 + 24 = ?</span>
            <div class="answer">答案: 71</div>
        </div>
        <div class="exercise">
            <span class="number">21. </span>
            <span class="expression">61 + 2 = ?</span>
            <div class="answer">答案: 63</div>
        </div>
        <div class="exercise">
            <span class="number">22. </span>
            <span class="expression">66 + 24 = ?</span>
            <div class="answer">答案: 90</div>
        </div>
        <div class="exercise">
            <span class="number">23. </span>
            <span class="expression">94 - 27 = ?</span>
            <div class="answer">答案: 67</div>
        </div>
        <div class="exercise">
            <span class="number">24. </span>
            <span class="expression">85 - 65 = ?</span>
            <div class="answer">答案: 20</div>
        </div>
        <div class="exercise">
            <span class="number">25. </span>
            <span class="expression">47 - 15 = ?</span>
            <div class="answer">答案: 32</div>
        </div>
        <div class="exercise">
            <span class="number">26. </span>
            <span class="expression">49 - 15 = ?</span>
            <div class="answer">答案: 34</div>
        </div>
        <div class="exercise">
            <span class="number">27. </span>
            <span class="expression">77 + 16 = ?</span>
            <div class="answer">答案: 93</div>
        </div>
        <div class="exercise">
            <span class="number">28. </span>
            <span class="expression">71 + 4 = ?</span>
            <div class="answer">答案: 75</div>
        </div>
        <div class="exercise">
            <span class="number">29. </span>
            <span class="expression">87 - 30 = ?</span>
            <div class="answer">答案: 57</div>
        </div>
        <div class="exercise">
            <span class="number">30. </span>
            <span class="expression">15 + 51 = ?</span>
            <div class="answer">答案: 66</div>
        </div>
        <div class="exercise">
            <span class="number">31. </span>
            <span class="expression">88 - 59 = ?</span>
            <div class="answer">答案: 29</div>
        </div>
        <div class="exercise">
            <span class="number">32. </span>
            <span class="expression">54 + 15 = ?</span>
            <div class="answer">答案: 69</div>
        </div>
        <div class="exercise">
            <span class="number">33. </span>
            <span class="expression">75 - 64 = ?</span>
            <div class="answer">答案: 11</div>
        </div>
        <div class="exercise">
            <span class="number">34. </span>
            <span class="expression">13 + 63 = ?</span>
            <div class="answer">答案: 76</div>
        </div>
        <div class="exercise">
            <span class="number">35. </span>
            <span class="expression">90 - 66 = ?</span>
            <div class="answer">答案: 24</div>
        </div>
        <div class="exercise">
            <span class="number">36. </span>
            <span class="expression">57 + 23 = ?</span>
            <div class="answer">答案: 80</div>
        </div>
        <div class="exercise">
            <span class="number">37. </span>
            <span class="expression">25 - 21 = ?</span>
            <div class="answer">答案: 4</div>
        </div>
        <div class="exercise">
            <span class="number">38. </span>
            <span class="expression">36 + 22 = ?</span>
            <div class="answer">答案: 58</div>
        </div>
        <div class="exercise">
            <span class="number">39. </span>
            <span class="expression">24 + 4 = ?</span>
            <div class="answer">答案: 28</div>
        </div>
        <div class="exercise">
            <span class="number">40. </span>
            <span class="expression">94 - 35 = ?</span>
            <div class="answer">答案: 59</div>
        </div>
        <div class="exercise">
            <span class="number">41. </span>
            <span class="expression">78 - 41 = ?</span>
            <div class="answer">答案: 37</div>
        </div>
        <div class="exercise">
            <span class="number">42. </span>
            <span class="expression">12 - 9 = ?</span>
            <div class="answer">答案: 3</div>
        </div>
        <div class="exercise">
            <span class="number">43. </span>
            <span class="expression">48 - 7 = ?</span>
            <div class="answer">答案: 41</div>
        </div>
        <div class="exercise">
            <span class="number">44. </span>
            <span class="expression">33 + 32 = ?</span>
            <div class="answer">答案: 65</div>
        </div>
        <div class="exercise">
            <span class="number">45. </span>
            <span class="expression">65 - 13 = ?</span>
            <div class="answer">答案: 52</div>
        </div>
        <div class="exercise">
            <span class="number">46. </span>
            <span class="expression">87 - 58 = ?</span>
            <div class="answer">答案: 29</div>
        </div>
        <div class="exercise">
            <span class="number">47. </span>
            <span class="expression">55 + 11 = ?</span>
            <div class="answer">答案: 66</div>
        </div>
        <div class="exercise">
            <span class="number">48. </span>
            <span class="expression">39 - 23 = ?</span>
            <div class="answer">答案: 16</div>
        </div>
        <div class="exercise">
            <span class="number">49. </span>
            <span class="expression">74 - 42 = ?</span>
            <div class="answer">答案: 32</div>
        </div>
        <div class="exercise">
            <span class="number">50. </span>
            <span class="expression">72 - 28 = ?</span>
            <div class="answer">答案: 44</div>
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